JP2024065408A - Construction method for cylindrical structure - Google Patents

Abstract

To provide a construction method for a cylindrical structure, which uses a temporary roof simplifying installation work and removal work.SOLUTION: In a construction method for a cylindrical structure 10 comprising a plurality of cylindrical bodies 11, a step of arranging an annular temporary roof body 21 having a penetration part 22 so as to cover an opening part of the cylindrical body 11 positioned at an upper end of the cylindrical structure 10 from above, and a step of installing the new cylindrical body 11 after removing the temporary roof body 21 are repeated. In a state in which the temporary roof body 21 is arranged on the cylindrical body 11 positioned at the upper end, a crane operation for the temporary roof body 21 is performed by making use of the penetration part 22.SELECTED DRAWING: Figure 7

Description

The present invention relates to a method for constructing a cylindrical structure.

During the construction of a cylindrical structure consisting of multiple cylinders, such as the tower of a wind power generator, a temporary roof is installed to cover the opening of the cylinder located at the top, one of the purposes of which is to prevent rainwater from entering the inside of the cylinder. Conventional temporary roofs include prefabricated ones made of steel plates, as well as temporary roofs made of balloons, as described in Patent Document 1.

Japanese Patent Application Laid-Open No. 10-196160

The above-mentioned prefabricated temporary roof and the temporary roof described in Patent Document 1 require complicated installation and removal procedures. Therefore, there has been a demand for a method of constructing a cylindrical structure using a temporary roof that can be easily installed and removed.

The construction method for a cylindrical structure that solves the above problem is a construction method for a cylindrical structure composed of multiple cylinders, which repeats the steps of placing a ring-shaped temporary roof body having a penetration part so as to cover from above the opening part of the cylinder located at the upper end of the cylindrical structure, and removing the temporary roof body and then installing a new cylinder, and performs a slinging operation for the temporary roof body using the penetration part when the temporary roof body is placed on the cylinder located at the upper end.

The present invention simplifies the installation and removal of temporary roofs.

FIG. 2 is a schematic diagram showing the installation state of a temporary roof device used in one embodiment of a method for constructing a tubular structure. FIG. 2 is a perspective view showing a schematic configuration of the temporary roof device. FIG. 13 is a top view showing an example of the position of a tethering mechanism that tethers the roof body to the cylindrical body. FIG. 2 is a diagram showing a schematic configuration of a tethering mechanism. 1 is a flow chart illustrating an example of a method for installing a temporary roof device. 13 is a diagram showing a schematic diagram of a roof side sling connected to a lifting sling on the ground. FIG. 13 is a diagram showing a schematic view of how work is performed using a penetration portion. FIG. 2 is a perspective view showing a schematic installation state of the temporary roof device. 4 is a flow chart showing an example of a method for removing the temporary roof device. 1 is a flowchart showing an example of a method for constructing a tubular structure.

One embodiment of a method for constructing a tubular structure will now be described with reference to Figures 1 to 10.
As shown in Figure 1, a construction method for a tubular structure 10 uses a temporary roof device 20. The temporary roof device 20 is installed at the upper end of the tubular structure 10 under construction to prevent rainwater from entering the internal space of the tubular structure 10. The tubular structure 10 is composed of a plurality of cylindrical bodies 11 connected in the vertical direction. The temporary roof device 20 includes a roof main body 21. The roof main body 21 is positioned so as to cover from above the upper opening portion of the cylindrical body 11 located at the upper end of the tubular structure 10.

As shown in FIG. 2, the roof body 21 is formed in an annular shape with a penetration 22 in the center. The penetration 22 is formed in a circular cross section with a size that allows workers to pass through with ease, for example, a diameter of about 1 m. The upper end opening 23 of the penetration 22 is formed by a raised portion that is raised above the surrounding area. In the following, the direction around the penetration 22 in the roof body 21 when viewed from above is referred to as the circumferential direction.

The roof body 21 is of an air-injection type. The roof body 21 has a contracted state in which the air is released and an expanded state in which air is injected. Figures 1 and 2 show the roof body 21 in the expanded state. The roof body 21 can be folded in the contracted state, allowing it to be transported between work sites in a compact state.

The temporary roof device 20 is equipped with an opening/closing door 25. The opening/closing door 25 is attached to the upper surface 21a of the roof body 21. The opening/closing door 25 is a door that opens and closes the upper end opening 23 of the penetration part 22. The opening/closing door 25 is configured so that it can be locked and unlocked from the inside of the penetration part 22. The opening/closing door 25 is formed in a shape that covers the entire upper end opening 23 of the penetration part 22 from above. Closing the opening/closing door 25 makes it difficult for rainwater to enter the internal space of the cylindrical body 11 from the penetration part 22.

The temporary roof device 20 is equipped with a lifting jig 27. The lifting jig 27 is provided on the upper surface 21a of the roof body 21. More specifically, the lifting jig 27 is provided at a position close to the outer periphery of the roof body 21, at equal intervals in the circumferential direction of the roof body 21. At least three lifting jigs 27 are provided. In this embodiment, four lifting jigs 27 are provided. The lifting jig 27 is configured so that the base end of the roof side sling 28 can be attached and detached.

The temporary roof device 20 is provided with a temporary fixing jig 30. The temporary fixing jig 30 is provided on the upper surface 21a of the roof body 21. More specifically, the temporary fixing jig 30 is provided between the through-hole 22 and each lifting jig 27 so as to surround the upper end opening 23 of the through-hole 22. The temporary fixing jig 30 is provided at a position that can be reached by a worker leaning out from the through-hole 22. The temporary fixing jig 30 is configured so that the tip of the roof side sling 28 can be attached and detached. The tip of the roof side sling 28 is attached to the temporary fixing jig 30 when the roof body 21 is in an installed state. The tip of the roof side sling 28 is removed from the temporary fixing jig 30 when the roof body 21 is lifted. It is preferable that carabiners or the like are provided at both ends of the roof side sling 28 so that it is securely connected to each jig 27, 30 and can be easily attached and detached.

As shown in FIG. 3, the temporary roof device 20 includes a tethering mechanism 35. The tethering mechanisms 35 are provided at equal intervals around the circumference of the roof body 21. The tethering mechanism 35 tethers the roof body 21 arranged at the upper end of the cylindrical body 11. A connecting flange 12 is provided on the inner circumference of the upper end of the cylindrical body 11 and is used to connect to the cylindrical body 11 arranged at the upper level. The connecting flange 12 has fastening holes 13 that penetrate in the vertical direction and are formed at predetermined intervals around the circumference of the cylindrical body 11. The tethering mechanism 35 uses the fastening holes 13 to tether the roof body 21.

As shown in FIG. 4 , the anchoring mechanism 35 includes an anchoring jig 36 , a fastening member 37 , an auxiliary anchoring member 38 , and a wire 39 .
The mooring jig 36 is provided on the underside 21b of the roof main body 21. More specifically, the mooring jig 36 is provided at a position near the outer periphery of the roof main body 21 and at a position where it can be arranged inside all of the cylindrical bodies 11 that constitute the cylindrical structure 10 when viewed from above.

The fastening member 37 has a bolt 40 and a nut 41. The bolt 40 has a shaft portion that passes through the fastening hole 13 and a head portion that engages with the upper surface 12a of the connecting flange 12. The head portion of the bolt 40 abuts against the lower surface portion 21b of the roof body 21. The nut 41 is fastened to the shaft portion of the bolt 40 from the underside of the connecting flange 12.

The anchoring auxiliary member 38 is fastened to the underside of the connecting flange 12 by a fastening member 37. The anchoring auxiliary member 38 is, for example, a plate material. The anchoring auxiliary member 38 is arranged so as to extend toward the anchoring jig 36 when viewed from above. The base end of a wire 39 is attached to the tip of the anchoring auxiliary member 38. The tip of the wire 39 is attached to the anchoring jig 36 of the roof main body 21. This wire 39 may be provided with a ratchet or the like for adjusting the tension.

The temporary roof device 20 configured in this way is delivered to the construction site with the roof body 21 and the anchoring mechanism 35 as separate entities. At this time, the roof body 21 is delivered in a contracted state. The roof body 21 may also be delivered in a folded state. The roof side sling 28 may also be attached to the roof body 21. The anchoring mechanism 35 is delivered to the construction site in a disassembled state.

(Installation method)
An example of a method for installing the temporary roof device 20 at a construction site will now be described.
As shown in FIG. 5, the installation method of the temporary roof device 20 includes a preparation step (step S101), a lifting step (step S102), a tethering step (step S103), and a temporary fastening step (step S104).

In the preparation process (step S101), air is injected to expand the roof body 21. The roof side sling 28 may be attached after expansion. In addition, inside the cylinder 11 located at the upper end of the tubular structure 10, scaffolding is installed for performing work such as connecting the cylinders 11 to each other. This scaffolding is used to perform preparation work for the anchoring mechanism 35. Specifically, an anchoring auxiliary member 38 with a wire 39 attached is fastened with a fastening member 37 to the connecting flange 12 of the cylinder 11 located at the upper end of the tubular structure 10.

As shown in FIG. 6, in the lifting process (step S102), a slinging operation is performed to connect the ends of each roof side sling 28 to the lifting sling 45. After that, the roof body 21 is lifted using a crane or the like and pulled up to the top end of the cylindrical structure 10. The roof body 21 is then positioned so as to cover the upper opening of the cylindrical body 11 and to abut from above against the heads of each bolt 40 that constitutes the anchoring mechanism 35. As a result, the roof body 21 is supported from below by the fastening members 37, specifically the heads of the bolts 40.

In the anchoring process (step S103), the tip of the wire 39 is connected to the anchoring jig 36, and then the tension of the wire 39 is adjusted. As a result, the roof body 21 is anchored to the cylindrical body 11 while covering the upper opening of the cylindrical body 11.

As shown in FIG. 7, in the temporary fastening process (step S104), a worker 50 opens the opening and closing door 25 of the roof body 21. After that, the worker 50 leans his upper body out of the penetration part 22 and connects the tip of the roof side sling 28 to the temporary fastening jig 30.

Then, as shown in FIG. 8, the tip of the roof-side sling 28 is detached from the hanging sling 45, and the opening and closing door 25 is closed and locked. In this way, the temporary roof device 20 is installed at the top end of the tubular structure 10 under construction.

(Removal method)
An example of a method for removing the temporary roof device 20 will be described.
The method of removing the temporary roof device 20 includes a sling connection step (step S201), a tether release step (step S202), a pull-down step (step S203), and a tether mechanism dismantling step (step S104).
In the sling connecting step (step S201), the worker 50 opens the opening/closing door 25 of the roof body 21. Then, the worker 50 leans his upper body out of the penetration portion 22 and removes the tip of the roof side sling 28 from the temporary fixing jig 30, and then connects the tip of the roof side sling 28 to the tip of the hanging sling 45. The worker 50 then closes and locks the opening/closing door 25.

In the mooring release step (step S202), the connection of the tip of the wire 39 to the mooring jig 36 is released. This makes the roof main body 21 ready to be lifted.
In the lowering process (step S203), the roof main body 21 is lowered to the ground using a crane or the like, and then the tip of the roof side sling 28 is removed from the hanging sling 45. The tip of the removed roof side sling 28 may be connected to the temporary fixing jig 30.

In the tethering mechanism dismantling process (step S204), the fastening member 37 is released, and the tethering auxiliary member 38 and the fastening member 37 are removed from the connecting flange 12 of the cylindrical body 11. This causes the tethering mechanism 35 to be dismantled.

When the temporary roof device 20 is removed in this manner, work such as connecting the upper tubular body 11 is carried out. The anchoring support member 38 and the fastening member 37 may be moved to the ground, or may be moved to a scaffolding that will be installed on the upper tubular body 11 after the upper tubular body 11 is installed.

(Method of constructing a cylindrical structure)
As shown in Fig. 10, in the method of constructing a tubular structure 10 using the temporary roof device 20 described above, the tubular body 11 is installed (step S301). Next, the temporary roof device 20 is installed using the installation method described above based on the progress of the construction work at that time (step S302). Then, after removing the temporary roof device 20 using the removal method described above (step S303), a new tubular body 11 is installed on the upper side of the upper end tubular body 11 (step S301). The installation of the tubular body 11, the installation and removal of the temporary roof device 20 are repeated in this manner to construct the tubular structure 10.

(Action)
The temporary roof device 20 is installed on the upper end of the tubular structure 10 according to the progress of the construction, thereby preventing rainwater from entering the internal space of the tubular structure 10. Construction of the tubular structure 10 is resumed after the temporary roof device 20 is removed.

The effects of this embodiment will be described.
(1) With the temporary roof device 20, the roof body 21 is placed on the upper end of the cylindrical structure 10, and then the upper opening of the cylindrical structure 10 can be covered simply by tethering it to the cylindrical body 11 with the tethering mechanism 35. In addition, since slinging work can be performed using the penetration parts 22, there is no need to install scaffolding or the like in the external area of the cylindrical body 11. As a result, installation and removal work can be simplified.

(2) The roof body 21 is anchored to the connecting flange 12 of the cylindrical body 11 by the anchoring mechanism 35. This eliminates the need to install a jig to fix the roof body 21 on the cylindrical body 11, simplifying the configuration of the temporary roof device 20 itself.

(3) The base end of the wire 39 is attached to the connecting flange 12 via the anchoring auxiliary member 38. This makes it easy to connect the connecting flange 12 and the wire 39. In addition, the length of the wire 39 can be shortened, which improves the ease of handling of the wire 39.

(4) The anchoring jig 36 is provided in a position that allows it to be placed inside all of the cylindrical bodies 11 that make up the cylindrical structure 10. This eliminates the need to replace the roof body 21 during construction of the cylindrical structure 10.

(5) Because the roof body 21 is an air-injection type, the roof body 21, and therefore the temporary roof device 20, can be transported in a compact state. In addition, the weight of the roof body 21 can be reduced.

(6) In the temporary roof device 20, the roof body 21 is inflated at the ground level. This eliminates the need to install a compressor, air supply pipe, etc., at the top end of the tubular structure 10. As a result, the installation work of the roof body 21 can be further simplified.

(7) A gap is formed between the roof body 21 and the cylindrical body 11, the size of which is equal to the head of the bolt 40. This allows ventilation of the internal space of the cylindrical structure 10 through the gap. As a result, the burden on workers can be reduced even when work is performed inside the cylindrical body 11 with the temporary roof device 20 still installed.

(8) Since the wire 39 is provided with a ratchet, the tension of the wire 39 can be easily adjusted.
(9) Since the opening/closing door 25 is configured to be lockable, it is possible to prevent the opening/closing door 25 from being opened due to strong winds or the like after the roof body 21 is installed.

This embodiment can be modified as follows: This embodiment and the following modifications can be combined with each other to the extent that there is no technical contradiction.
In the above embodiment, the roof body 21 is an air-injection type. However, the roof body 21 is not limited to this, and may be any type that can be lifted from the ground and placed on the upper end of the cylindrical structure 10, and may be made of, for example, a thin steel plate.

- The roof body 21 may be replaced depending on the size of the cylinder 11 located at the upper end. Even with this configuration, it is only necessary to replace the roof body 21, so the installation and removal work is not complicated.

- The anchoring mechanism 35 may be configured so that the wire 39 is fastened to the connecting flange 12 by a fastening member 37, or the nut 41 may be provided with a portion to which the base end of the wire 39 can be connected.

The technical ideas that can be understood from the above-described embodiment and modified examples will be described.
(Appendix 1)
The cylinder has a connecting flange on the inner periphery of its upper end that is used to connect with a cylinder placed in the upper stage, and with the temporary roof body placed on the cylinder located at the upper end, the slinging work is performed with the temporary roof body tethered to the connecting flange. This allows the temporary roof body to be installed safely.

(Appendix 2)
The temporary roof body has a lifting jig to which the base end of the roof side sling is connected at a position near the outer periphery of the upper surface, and a temporary fixing jig to which the tip of the roof side sling is temporarily fixed at a position between the penetration part and the lifting jig on the upper surface, and is lifted with the tip of the roof side sling connected to a hanging sling, and the tip of the roof side sling is replaced from the hanging sling to the temporary fixing jig while the temporary roof body is tethered to the connecting flange. This allows the roof side sling to be replaced safely.

(Appendix 3)
The temporary roof body is an air-injection type, and air is injected into the temporary roof body on the ground. This eliminates the need to move the device and piping for injecting air into the temporary roof body to the top of the cylindrical structure, and allows the temporary roof body to be installed smoothly.

10...Cylindrical structure, 11...Cylindrical body, 12...Connecting flange, 12a...Top surface, 13...Fastening hole, 20...Temporary roof device, 21...Roof body, 21a...Top surface, 21b...Bottom surface, 22...Penetration, 23...Top opening, 25...Opening door, 27...Lifting tool, 28...Roof side sling, 30...Temporary fastening tool, 35...Anchoring mechanism, 36...Anchoring tool, 37...Fastening member, 38...Anchoring auxiliary member, 39...Wire, 40...Bolt, 41...Nut, 45...Lifting sling, 50...Worker.

Claims (2)

A method for constructing a cylindrical structure composed of a plurality of cylindrical bodies, comprising the steps of:
A step of placing an annular temporary roof body having a penetration portion so as to cover from above an opening portion of the cylindrical body located at the upper end of the cylindrical structure;
The step of removing the temporary roof body and then installing a new cylindrical body is repeated,
A method for constructing a tubular structure, comprising the steps of: placing the temporary roof body on the tubular body located at the upper end; and performing slinging work on the temporary roof body using the penetration portion. An opening and closing door for opening and closing the penetration part is attached to the upper surface part of the temporary roof body,
The method for constructing a cylindrical structure according to claim 1 , wherein the slinging work is performed by opening the opening and closing door.

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